MET Q18 - Fronts and Frontal Depressions

Question 1

The approximate seasonal latitude of the polar front in the northern hemisphere is:
Question 1 Select one:

a.Summer - 60N; Winter - 50N

b.All year - 60N

c.Summer - 40N; Winter - 30N

d.Summer - 40N; Winter - 60N

Answer 1

a.Summer - 60N; Winter - 50N

Question 2

The approximate geographical position of the Atlantic Polar front in winter in the northern hemisphere is:
Select one:

a.SE Greenland to SW UK

b.E Brazil to W Spain

c.Florida to SW UK

d.Canada to Norway

Answer 2

c.Florida to SW UK

Question 3

Which of the following conditions are you most likely to encounter when approaching an active warm front at medium to low level?
Select one:

a.Severe turbulence and cloud to ground lightning

b.Severe thunderstroms at low altitude

c.low cloud base and poor visibility

d.high cloud base, good surface visibility and isolated thunderstorms

Answer 3

c.low cloud base and poor visibility

Question 4

The surface visibility in the warm sector of a polar front depression is likely to be
Select one:

a.less than 1km

b.Approx 20km

c.approx 50km

d.Less than 10km

Answer 4

d.Less than 10km

Question 5

How far ahead of the surface position of a warm front will the precipitation band typically extend?
Select one:

a.Approx 400nm (600km)

b.Approx 200nm (300km)

c.Approx 500nm (800km)

d.Approx 100nm (150km)

Answer 5

b.Approx 200nm (300km)

Question 6

Which of the following combinations is most characteristic of unstable polar maritime air behind a cold front?
Select one:

a.Poor visibility, continuous precipitation, stratiform cloud

b.Poor visibility, intermittent precipitation, cumuliform cloud

c.Good visibility between showers, cumuliform cloud

d.Good visibility between showers, stratiform cloud

Answer 6

c.Good visibility between showers, cumuliform cloud

Question 7

The hazards typically associated with a cold front are
Select one:

a.Light to moderate icing

b.FG and Inversions

c.Hoar frost and heavy precipitation

d.Mod to severe turbulence and icing

Answer 7

d.Mod to severe turbulence and icing

Question 8

When a frontal depression occludes to form a warm occlusion, the point of occlusion exists
Select one:

a.ahead of the coldest air mass

b.ahead of the warm sector

c.behind the warm sector

d.behind the coldest air mass

Answer 8

d.behind the coldest air mass

Question 9

The wind direction associated with a quasi-stationary front is
Select one:

a.at right angles to the front above the friction layer

b.parallel to the front in opposite directions either side

c.parallel to the front in the same direction on both sides

d.perpendicular towards the front on eitherside

Answer 9

b.parallel to the front in opposite directions eitherside

Question 10

The direction of a polar front depression can be determined by the wind direction
Select one:

a.ahead of the warm front

b.at the apex of the frontal wave

c.behind the cold front

d.in the warm sector

Answer 10

d.in the warm sector

Question 11

On the passage of a frontal depression over the UK the surface wind direction will
Select one:

a.back at the warm front and back at the cold front

b.veer at the warm front and veer at the cold front

c.veer at the warm front and back at the cold front

d.back at the warm front and veer at the cold front

Answer 11

b.veer at the warm front and veer at the cold front

Question 12

With the passage of a cold front the surface pressure will
Select one:

a.increase

b.stay the same

c.increase briefly then decrease

d.decrease

Answer 12

a.increase